Convertible Top Closing Hard

StudioWizard · Post by **StudioWizard** » Tue May 30, 2023 4:59 am

My convertible top seems like it crashes down pretty hard when it's latching onto the top of the windscreen. Is this normal or should it be gently dropping it down?

Also, when it fully retracts to open, it doesn't quite make it to the latch. I usually give it a little shove at the end and I hear it click in. If I don't do that, sometimes the open button flashes red meaning it's not fully retracted.

Is there some basic maintenance I can/should be doing with the mechanism? It works perfectly otherwise as fas as I can tell.

Thanks!!

Craneman · Post by **Craneman** » Thu Jun 01, 2023 9:34 pm

StudioWizard · Post by **StudioWizard** » Thu Jun 01, 2023 10:12 pm

Craneman: is yours also doing this?

Matty_Z4 · Post by **Matty_Z4** » Fri Jun 02, 2023 12:09 am

Slamming sounds like the roof tensioning straps. See this post viewtopic.php?p=1265601#p1265601

Not locking when open could be the roof not folding correctly. There is a plastic thing in the stitching above the windows that help the roof fold correct if they are broken or missing it could cause your problem.

StudioWizard · Post by **StudioWizard** » Fri Jun 02, 2023 1:57 am

OK, I'm diving in! Just checked out that thread which lead to other threads and what appears to be either a factory defect or common age problem with "roof tensioning belts". Here are the part #s:

Tension Cable - BMW 54-34-7-079-587 (left)
Tension Cable - BMW 54-34-7-079-588 (right)

It might be a PITA to replace these.... still researching. haha

For now, I've been "catching" the roof just before it slams down. It can't be good for the parts to hit like that. haha

smorris_12 · Post by **smorris_12** » Fri Jun 02, 2023 8:16 am

The front of mine sort of flops forward as it's shutting, taps the windscreen frame quite hard and bounces back. I presume this is what people describe.

It looks a bit of a pain of a job but using the old straps to pull the new ones thru ought to be feasible.

Matty_Z4 · Post by **Matty_Z4** » Fri Jun 02, 2023 12:58 pm

smorris_12 wrote: ↑Fri Jun 02, 2023 8:16 am The front of mine sort of flops forward as it's shutting, taps the windscreen frame quite hard and bounces back. I presume this is what people describe.

It looks a bit of a pain of a job but using the old straps to pull the new ones thru ought to be feasible.

Pretty much as soon as gravity takes over the top seems to accelerate into the top of the windscreen frame. A bit like this.

And apparently this one has had the roof tensioners replaced

This is the result of performing Service Bulletin:

SI B54 14 07 Soft Top Slams Down on the Cowl when Closing.

I wish both videos were taken from the same angle inside the car, as you can still hear the roof locator pins thwack into their locating holes.

Craneman · Post by **Craneman** » Fri Jun 02, 2023 7:32 pm

StudioWizard wrote: ↑Thu Jun 01, 2023 10:12 pm Craneman: is yours also doing this?

oh yes, hits that screen top hard. Does yours fully open.?

StudioWizard · Post by **StudioWizard** » Fri Jun 02, 2023 8:14 pm

Craneman wrote: ↑Fri Jun 02, 2023 7:32 pm

oh yes, hits that screen top hard. Does yours fully open.?
[/quote]

Yes, it opens and closes great EXCEPT for the slamming when closing and not quite latching when it opens. I usually push it down lightly when it's settling until I hear it click.

I'm trying to locate service instructions for lubricating and adjusting the mechanisms for optimal performance, but haven't found anything yet. I'm going to ask ChatGPT.

bigwinn · Post by **bigwinn** » Fri Jun 02, 2023 8:17 pm

I know rob

zulu4

did this job on his car a while back

And a write up? Worth a search

StudioWizard · Post by **StudioWizard** » Sun Jun 04, 2023 11:50 pm

StudioWizard wrote: ↑Fri Jun 02, 2023 1:57 am OK, I'm diving in! Just checked out that thread which lead to other threads and what appears to be either a factory defect or common age problem with "roof tensioning belts". Here are the part #s:

Tension Cable - BMW 54-34-7-079-587 (left)
Tension Cable - BMW 54-34-7-079-58 (right)

[EDIT 6/4/23: the above part numbers might not be correct. Will update post when confirmed.]

It might be a PITA to replace these.... still researching. haha

For now, I've been "catching" the roof just before it slams down. It can't be good for the parts to hit like that. haha

StudioWizard · Post by **StudioWizard** » Sun Jun 04, 2023 11:51 pm

StudioWizard wrote: ↑Sun Jun 04, 2023 11:50 pm
StudioWizard wrote: ↑Fri Jun 02, 2023 1:57 am OK, I'm diving in! Just checked out that thread which lead to other threads and what appears to be either a factory defect or common age problem with "roof tensioning belts". Here are the part #s:

Tension Cable - BMW 54-34-7-079-587 (left)
Tension Cable - BMW 54-34-7-079-588 (right)

[EDIT 6/4/23: the above part numbers might not be correct. Will update post when confirmed.]

It might be a PITA to replace these.... still researching. haha

For now, I've been "catching" the roof just before it slams down. It can't be good for the parts to hit like that. haha

StudioWizard · Post by **StudioWizard** » Mon Jun 05, 2023 12:11 am

StudioWizard wrote: ↑Sun Jun 04, 2023 11:50 pm
StudioWizard wrote: ↑Fri Jun 02, 2023 1:57 am OK, I'm diving in! Just checked out that thread which lead to other threads and what appears to be either a factory defect or common age problem with "roof tensioning belts". Here are the part #s:

Tension Cable - BMW 54-34-7-079-587 (left)
Tension Cable - BMW 54-34-7-079-58 (right)

[EDIT 6/4/23: the above part numbers might not be correct. Will update post when confirmed.]
Here's the correct part #: 54 34 7 184 482

It might be a PITA to replace these.... still researching. haha

For now, I've been "catching" the roof just before it slams down. It can't be good for the parts to hit like that. haha

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